Modifiers for coatings, adhesives or sealants

ABSTRACT

Modifier composition for coating compositions or non-coating compositions such as adhesives, inks, sealants, flooring and composites which have been derived from pure feedstock comprising phenol, alpha-methyl styrene and vinyl toluene and which show a sufficient storage stability in combination with an attractively low viscosity, high performance coating, adhesive, sealant, ink, flooring and composite compositions, comprising said modifier composition, and shaped articles, bearing on their surface said coating, adhesive, ink or sealant composition in uncured or cured state, or shaped articles derived from the flooring or composite compositions in uncured or cured state

The invention relates to improved modifiers for coating applications andnon-coating applications such as adhesives, sealants, ink and flooringor composite compositions etc. and more in particular to modifiers forcoatings based on thermoplastic resin binder systems or thermo hardeningresin and curing agent binder systems, such as those based on epoxyresin, alkyd resin, polyester resin, polyurethane resin or acrylicresin, together with a curing or cross linking agent.

Said modifiers were for several years prepared from phenol and C9/C10hydrocarbons and were in particular applied in coating compositions,based on binders, comprising epoxy resins and curing agents. Originallysaid modifiers were based on phenol and hydrocarbons having 9 and/or 10carbon atoms.

Typical examples thereof are NOVARES LA 300, 500, 700, 1000 (availablefrom Rütgers VFT AG, Duisburg, Germany).

The main disadvantage of said conventional modifiers are the relativelylow OH functionality (0.2-0.5) and the dark color.

Hydrocarbon resin modifiers, principally suitable for white and/or lightcolored paint systems, have been developed by using as startingfeedstock pure monomers, such as a-methyl styrene, instead of C9/C10monomers.

Typical examples of such resins are NECIRES EPX LT/LC (from NevcinPolymers BV, Uithoorn, the Netherlands).

Compared to the phenol/C9/C10 resins, the resins in question exhibit amuch better color (1-2 Gardner) and color stability, however, said resinexhibits a high tendency to crystallize.

Especially resins having a hydroxyl functionality of >0.5 exhibit a hightendency to crystallize.

Resins of aromatic/aliphatic nature, such as NEVOXY/Necires EPX-L, L2,L5, LH (Neville Chemical Company, Pittsburgh, USA//Nevcin Polymers BV,Uithoorn, the Netherlands), are light colored (1-2 Gardner), exhibitgood color stability and a low tendency to crystallize.

The main disadvantage of said resins is the relatively low hydroxylfunctionality (0.2-0.5).

Higher hydroxyl functional resins of this type are not very attractivein view of the relatively high level of aliphatic content required toimpart good storage stability.

As a result of the latter the use of such resins led to coatings beingtoo low in hardness.

Aromatic resins obtained by using o-cresol instead of phenol incombination with alpha methyl styrene as raw materials like NOVARESLX-200 (Rütgers VFT) have the advantages of a somewhat higher OHfunctionality (0.5-0.6).

Disadvantages of said resin are poor color and objectionably unpleasantodor.

Aromatic resin modifiers derived from phenol and styrene like NOVARESLS-500 (Rütgers VFT) possess a high hydroxyl functional (0.9-1.0).

A disadvantage of said resins are poor, unpleasant odor and thetoxicological characteristics of styrene.

In particular, in the modifier compositions derived from phenol,a-methyl styrene (AMS) and a dimer of isobutylene, alkylated phenolconstituents could be in the final compositions which would result fromthe reaction of one mole phenol, one mole AMS and one mole of dimer, andof one mole phenol and one mole dimer respectively.

The alkylated phenols are regulated in some countries and areobjectionable in others.

Regulations regarding alkylated phenols are expected to increaseworld-wide.

It will be appreciated by persons skilled in the art, that during thelast decade the actual function of the modifiers to be applied incoating, ink, adhesive, sealant etc. compositions have been graduallychanged from one of cost reduction of the final composition togetherwith improvement of certain performance properties into meeting thepresent low Volatile Organic Compounds (VOC) regulations withimprovement of certain performance properties.

Due to the increasing pressure from health and environmental authoritiesin most of the industrialized countries and the increasing economicalpressure for low cost modifiers there is still an increasing need toprovide further improved modifiers, which can meet the presentlyrequired combination of properties, i.e. light color, no odor or onlylow odor, sufficient reactivity in the final applications e.g. coatingcomposition, low tendency to crystallize during storage, an attractivelylow viscosity, i.e. <20.000 mPa.s at 25° C., the absence of(potentially) toxic reaction products in the final modifiercompositions, and less organic solvent in the final coating, adhesive orsealant etc. composition.

Therefore an object of the present invention is to provide said improvedmodifiers.

Said modifier compositions aimed at must show goodcompatibility/mix-ability with all applied types of resin bindermaterials (epoxy, alkyl, polyester, acrylics, polyurethane andthermoplastics) in the e.g. coating compositions etc., must show goodviscosity reduction, high dissolving/dilution power, must facilitatepigment wetting in the coating composition etc. and later on a goodsubstrate wetting when the coating composition is applied.

In addition said modifier compositions aimed at must enhance the curespeed of the binder system of the coating composition etc., must enablea sufficiently high shelf life of the coating composition etc., mustprovide a good balance of flexibility/hardness of the final cured film,must not deteriorate and preferably even enhance the adhesion and/orcorrosion resistance of the coating composition etc., and must enhancethe flow out of the coating composition etc.

Another objective of the present invention is to provide highperformance coating and non-coating compositions comprising saidimproved modifiers, binders, pigments, fillers and optional otherauxiliaries and optionally small amounts of solvents (i.e. less than 5wt %, relative to the complete compositions) and more preferably nosolvent at all.

Still another objective of the present invention is to provide shapedarticles, on the surfaces of which said coating composition andno-coating composition such as, adhesive, sealant, ink, flooring andcomposite compositions have been applied in uncured or cured state.

As result of extensive research and experimentation said improvedmodifiers aimed at have now been surprisingly found.

Accordingly the invention relates to low odor modifier composition forcoating or non-coating applications, which have been derived from purefeedstock comprising phenol, a-methyl styrene (AMS) and vinyl toluene(VT), and which show a sufficient storage stability in combination withan attractive low viscosity.

It will be appreciated that ortho vinyl toluene, para vinyl toluene, andmeta vinyl toluene or mixtures thereof can be used as the vinyl tolueneconstituent without other accompanying chemicals.

According to a preferred embodiment of the low odor modifiercompositions of the present invention substantially purepara-vinyl-toluene is included, which has found to provide improvedcolor to the modifiers and compatibility in the end-use compositions.

Preferably the low odor modifier composition of the present inventioncomprises phenol in a weight proportion of from 0.1 to 40 wt %, a-methylstyrene in a weight proportion of from 30 to 90 wt %, and vinyl toluenein a weight proportion from 0.1 to 36 wt %, wherein all specified weightproportions are relative to the weight of the complete modifiercomposition and the sum of the three proportions will always be 100%.

Still more preferably said respective weight proportions of phenol,a-methyl styrene and vinyl toluene are in the ranges of from 9 to 23 wt%, from 60 to 80 wt % and from 1 to 30 wt % respectively.

Preferred mutual molar ratios of phenol and vinyl toluene are in therange of from 1:0.2 to 1:0.80 and most preferred ratios are in the rangeof from 1:0.28 to 1:0.60.

Preferred mutual molar ratios of phenol and a-methyl styrene are in therange of from 1:0.50 to 1:8.0 and most preferred ratios are in the rangeof from 1:0.80 to 1:6.0.

It will be appreciated that the improved low odor modifier compositionsof the present invention have been found to be characterized by thepresence of only detectable amounts of generally recognized non-toxicand storage stable components.

This could surprisingly be reached by the replacement of part of theoriginally applied a-methyl styrene by a well defined, rather purechemical constituent which is free of other normally accompanyingorganic compounds, which contain 9 or 10 carbon atoms.

The modifier compositions of the present invention can be furthercharacterized by a dynamic viscosity at 25° C. in the range of from 100to 3000 mPa.s and preferably from 100 to 2000 mPa.s, a Gardner colorvalue <4 and preferably ≦2, an hydroxyl value of from 0.1 to 7.0 wt %and preferably from 1.5 to 6.5 wt %, and a functionality in the range offrom 0.05 to 1.0 and preferably from 0.2 to 0.8.

It has been surprisingly found now that the replacement of a-methylstyrene (AMS) by vinyl toluene (partly or completely) can provide lowodor modifier compositions, containing a relatively high content ofphenol and showing an excellent storage stability, i.e. showing nocrystallization after storage for 6 months or longer at 25° C., while anattractive viscosity of the modifier composition appeared to be reachedwhen an excess of AMS is used compared to vinyl toluene (Phenol/VT resinhas a high viscosity & Example E table 2).

Moreover, said modifier compositions have been found to provide asignificantly enhanced solubility in non-aromatic solvents, e.g. inisopropyl alcohol.

It will be appreciated that another aspect of the invention is formed byhigh performance coating composition and non-coating compositions,comprising at least one of the herein before specified improvedmodifiers together with a binder and optionally pigments, fillers andother auxiliaries, and as far as necessary small amounts of organicsolvents (i.e. less than 5 wt % relative to the weight of the completecomposition).

The binder in said composition can be based on an alkyd resin, polyesterresin epoxy resin together with a curing agent, polyurethane resin,acrylic resin, thermoplastic resin.

A further aspect of the present invention is formed by shaped articles,on the surface of which said coating, adhesive, ink, sealant flooring orcomposite compositions have been applied, or shaped articles derivedfrom the flooring or composite compositions, in uncured state or curedstate.

The modifier compositions of the present invention can be prepared bymixing and reacting the hereinbefore specified respective ingredients inany sequence into an inert organic solvent such as xylene, toluene andusing an acid catalyst.

However the more preferred preparation process comprises mixing andsubstantially complete reaction of the phenol and vinyl tolueneconstituent, of which the latter is gradually and slowly added to phenoldissolved in organic solvent, before AMS is slowly and gradually addedto the reaction mixture, followed by further reaction.

Resins made by the preferred method have shown somewhat better storagestability compared to those not prepared by the preferred method.

It will be appreciated that said preferred manufacturing process formsanother aspect of the present invention.

Therefore the invention also relates to a process for the manufacturingof the hereinbefore specified modifier compositions, comprising mixingphenol with an organic solvent, in a weight ratio of from 30:70 to 40:60and a catalyst, e.g. a Lewis acid catalyst and more preferably BF3Etherate, in an amount of from 0.01 to 0.2 wt %, at a temperature offrom 40 to 60° C., followed by a slow and gradual addition of apredetermined amount of vinyl toluene to the obtained solution over aperiod of from 0.25 to 0.75 hr under vigorous stirring, followed by anadditional reaction period of about 0.5 hours.

Then AMS is added gradually and slowly to the reaction mixture over aperiod of from 3 to 5 hrs, and after complete addition, an additionalreaction time of from 0.25 to 0.75 hrs, neutralizing and filtering thereaction mixture and removal of the organic solvent, occurring in thefinal reaction mixture in a weight proportion of from 10 to 25 wt %,relative to the weight of the complete reaction mixture.

The invention is illustrated by the following examples, however withoutrestricting its scope to these embodiments.

EXAMPLES 1-5 Example 1 General Preparation Procedure Composition I inTable I

Phenol (8.8 g) and xylene (14.8 g) were charged in a round bottom glassreactor, equipped with condenser, stirrer, and temperature control.

The mixture was heated to 50° C. and after homogenizing 0.05% w/w BF3catalyst was added.

After homogenizing a pre-prepared mixture of VT (3.1 g) and AMS (88.1)was added gradually and slowly to the reaction mixture in about 4 hourstime.

After complete addition the mixture was allowed to react for another 0.5hours.

Then the mixture was neutralized and filtered. After solvent removal theproduct was analyzed. Phenolic hydroxyl content: 1.5 wt % Viscosity,Brookfield 25° C.: 125 mPa · s Color, Gardner: 1

Example 2 Preferred Method Composition I in Table I

Phenol (8.8 g) and xylene (14.8 g) were charged in a round bottom glassreactor, equipped with condenser, stirrer, and temperature control.

The mixture was heated to 50° C. and after homogenizing 0.05% w/w BF3catalyst was added.

After homogenizing VT (3.1 g) was added gradually and slowly to thereaction mixture in about 0.5 hours time.

After complete addition the mixture was allowed to react for another 0.5hours.

Then AMS (88.1) was added gradually and slowly to the reaction mixturein about 4.0 hours time.

After complete addition the mixture was allowed to react for another 0.5hours.

Then the mixture was neutralized and filtered. After solvent removal theproduct was analyzed. Phenolic hydroxyl content: 1.5 wt % Viscosity,Brookfield 25° C.: 125 mPa · s Color, Gardner: 1

Example 3 General Preparation Procedure for Composition V in Table I

Phenol (8.8 g) and xylene (14.8 g) were charged in a round bottom glassreactor, equipped with condenser, stirrer, and temperature control.

The mixture was heated to 50° C. and after homogenizing 0.08% w/w BF3catalyst was added.

After homogenizing a pre-prepared mixture of VT (5.5 g) and AMS (24.0)was added gradually and slowly to the reaction mixture in about 3 hourstime.

After complete addition the mixture was allowed to react for another 0.5hours.

Then the mixture was neutralized and filtered. After solvent removal theproduct was analyzed. Phenolic hydroxyl content: 4.2 wt % Viscosity,Brookfield 25° C.: 500 mPa · s Color, Gardner: 1-2

Example 4 Preferred Method for Composition V in Table I

Phenol (8.8 g) and xylene (14.8 g) were charged in a round bottom glassreactor, equipped with condenser, stirrer, and temperature control.

The mixture was heated to 50° C. and after homogenizing 0.08% w/w BF3catalyst was added.

After homogenizing VT (5.5 g) was added gradually and slowly to thereaction mixture in about 0.75 hours time.

After complete addition the mixture was allowed to react for another 0.5hours.

Then AMS (24.1) was added gradually and slowly to the reaction mixturein about 2.5 hours time.

After complete addition the mixture was allowed to react for another 0.5hours.

Then the mixture was neutralized and filtered. After solvent removal theproduct was analyzed. Phenolic hydroxyl content: 4.2 wt % Viscosity,Brookfield 25° C.: 500 mPa · s Color, Gardner: 1-2

Example 5

Modifier compositions of the present inventions (I-VII, table I andcomparative compositions C and D (Table II) were prepared in one kgbatches as described in Examples 2 and 4 and as specified in the Table Iand II.

The composition is analyzed for viscosity, color, hydroxyl value,hydroxyl content, functionality, and storage stability.

The results are listed in Table I (Examples I-VII) and Table II(Comparative compositions C and D). In the comparative modifiercompositions A and B were prepared from phenol and AMS only.

The specific data and the results are listed in Table II (Comparativecompositions A and B). TABLE I Composition and characteristicsphenol/VT/AMS modifiers according to the present invention. Example I IIIII IV V VI VII Composition .(g) Phenol 8.8 8.8 8.8 8.8 8.8 8.8 8.8 VT3.1 3.1 3.1 4.8 5.5 5.9 6.1 AMS 86.1 43.5 26.6 41.8 24.0 14.6 8.8Composition details Phenol (% w) 8.8 15.9 22.9 15.9 23.0 30.0 37.1 VT*(% w) 3.1 5.5 8.0 8.8 14.4 20.0 25.7 AMS (% w) 88.1 78.6 69.1 75.3 62.650.0 37.2 Phenol:VT:AMS (molar ratio) 1:0.28:7.96 1:0.28:3.951:0.28:2.41 1:0.44:3.78 1:0.50:2.2 1:0.53:1.32 1:0.55:0.80 Hydroxyl-value (% w) 1.6 2.9 4.2 2.9 4.2 5.4 6.7 functionality (0.2) (0.4) (0.6)(0.4) (0.6) (0.8) (1.0) Performance properties Storage stability goodgood good good good good good Gardner color 1-2 1-2 1-3 1-2 1-3 2-4 2-4Solubility in IPA good good good good good good good Viscosity **25° C.in mPa · s 125 150 600 150 500 1000 2000*If para vinyl toluene is used instead of a technical mixture of thethree VT monomers, the Gardner color will always be 1-2**ASTM-D-1544

TABLE II Comparative Examples Comp. example A B C D E Composition (g)Phenol 8.8 8.8 8.8 8.8 8.8 VT 0.0 0.0 3.1 3.1 16.1 AMS 78.3 36.8 17.511.9 0.0 Composition details Phenol (% wt) 10.1 19.3 30.0 37.0 35.4 VT(% wt) 0.0 0.0 10.4 12.8 64.7 AMS (% wt) 89.9 62.6 59.6 50.2 0.0Phenol:VT:AMS (molar ratio) 1.0:0.0:7.08 1.0:0.0:3.3 1.0:0.28:1.581.0:0.28:1.08 1.0:1.46:0.0 Hydroxyl - value (% w) 1.8 3.5 5.4 6.7 6.4functionality (0.3) (0.5) (0.8) (1.0) (0.95) Performance propertiesStorage stability moderate/poor poor poor very poor good Gardner Color1-2 1-2 1-3 1-3 4-6 *Viscosity Brookfield mPa · s 25 C. 900 1500 — —20.000 Solubility in IPA in 50% solution poor poor good good good (hazesolution) (haze solution)*ASTM-D-1544

1. Low odor modifier compositions for coating or non-coatingapplications, which have been derived from pure feedstock, comprisingphenol, a-methyl styrene and ortho-, meta or para-vinyl toluene ormixtures thereof and which show a sufficient storage stability incombination with an attractive low viscosity.
 2. Modifier compositionaccording to claim 1, which comprise phenol in a weight proportion offrom 0.1 to 40 wt %, a-methyl styrene in a weight proportion of from 30to 90 wt %, and vinyl toluene in a weight proportion of from 0.1 to 36wt %, wherein all specified weight proportions are relative to theweight of the complete modifier composition and the sum of the threeproportions will always be 100%.
 3. Modifier composition according toclaim 2, wherein the weight proportions of phenol, a-methyl styrene andvinyl toluene are in the ranges of from 9 to 23 wt %, from 60 to 80 wt %and from 1 to 30 wt % respectively.
 4. Modifier composition according toclaim 1, wherein the mutual molar ratios of phenol and vinyl toluene arein the range of from 1:0.20 to 1:0.80.
 5. Modifier composition accordingto claim 4, wherein the mutual molar ratios of phenol and vinyl tolueneare in the range of from 1:0.28 to 1:0.60.
 6. Modifier compositionaccording to claim 1, wherein the mutual molar ratios of phenol anda-methyl styrene are in the range of from 1:0.50 to 1:8.0.
 7. Modifiercomposition according to claim 6, wherein the mutual molar ratios ofphenol and a-methyl styrene are in the range of from 1:3.2 to 1:8.0. 8.Modifier composition according to claim 1, characterized by a dynamicviscosity at 25° C. in the range of from 100 to 2000 mPa.s, a Gardnercolor value <4, an hydroxyl value of 0.1 to 7.0 and a functionality inthe range of from 0.05 to 1.0.
 9. Modifier composition according toclaim 8, characterized by a dynamic viscosity at 25° C. in the range offrom 100 to 2000 mpa.s, a Gardner color value <2, an hydroxyl value of1.5 to 6.5 and a functionality 0.2 to 0.8.
 10. High performance coatingor non coating compositions, comprising at least one of the modifiercompositions of claims 1-9, together with a binder and optionallypigments, fillers and auxiliaries and if necessary small amounts oforganic solvents (less than 5 wt %, relative to the weight of thecomplete composition).
 11. Shaped articles, bearing on their surface acoating composition of claim 10, in uncured or cured state, or shapedarticles derived from the flooring or composite compositions of claim10, in uncured or cured state.
 12. A process for the manufacturing ofthe here in before specified modifier compositions, comprising mixingphenol with an organic solvent, in a weight ratio of from 30:70 to 40:60and a acid catalyst, e.g. a Lewis acid catalyst, in an amount of from0.01 to 0.2 wt %, at a temperature of from 40 to 60° C., followed by aslow and gradual addition of a predetermined amount of methyl styrene tothe obtained solution over a period of from 0.25 to 0.75 hr undervigorous stirring, followed by an additional reaction period of from 3to 5 hrs, and after complete addition, an additional reaction time offrom 0.25 to 0.75 hrs, neutralizing and filtering the reaction mixtureand removal of the organic solvent by distillation.